No view support apparently generated for adding an entity to a 'hasMany' association

With a simple Book / Author example it seems that the scaffolded 'create new author' view is not rendering a provision for adding a 'book' (created on the spot, or already existing in the system) to the 'hasMany books' association. I'm using Grails 3.1.2 with scaffolding plugin 3.2.1 . Here is my use case:

// Model
class Book {
String title
}

class Author {
String name
static hasMany = [books: Book]
}

// Controllers
class BookController {
static scaffold = Book
}

class AuthorController {
static scaffold = Author
}

I certainly might be missing something but with such a straightforward example I'm wondering if this might be a bug with either the scaffolding plugin, grails, or the interaction between the two...

Reproduce the Book and Author example with Grails 3.1.2 and scaffolding plugin 3.2.1, then inspect the generated Author create view and its handling of the hasMany books association. Compare the behavior for creating a new Book and selecting an existing one; done means the expected association controls are rendered or the missing support is clearly confirmed.

Written by the indexing model from the issue text.